Many steel products, such as steel sheets or corrugated steel panels, are typically formed into discrete sections on a continuous-feed roll forming line. Each section exits the line and rolls onto a drop stacking machine which has a number of roller supports. When the trailing edge of the steel section has exited the roll forming line, the roller supports on the drop stacking machine retract or swing out of the way, thus dropping the steel section onto the stack below. In order to simplify bundling or packaging of the stack for handling and subsequent transport, it is desirable that at least one end of the pile is straight or justified.
One common way by which to justify the stack is to physically tamp the section ends each time a new section is dropped onto the pile. Unfortunately, the tamping method tends to damage one end of the steel sections, and only works well when all of the sections are of the same overall length. Moreover, the tamping method requires a physical stop at the leading edge, which must be adjusted manually in order to accommodate the variety of lengths that may be produced on the roll forming line. Accordingly, there exists a need for an improved justifying device for a drop stacking machine.